Traditionally, all of the lightest weight bags are made with the extremely light ripstop nylons. We created our Caribou MF to be lightweight, durable, and comfortable by using our lightweight Microfiber material. This 1 lb. 4 oz. mummy bag has a full length zipper and is cut wider than average for broader shoulders and a more comfortable fit. With its breathable, water resistant outer shell, the Caribou MF is a great lightweight summer bag and a perfect choice for AT hikers.

I recently used my Caribou (taffeta) bag on a trip to California's Trinity Alps Wilderness. I wanted to keep my pack under 35 pounds for 3-day trip with food and water.

Western Mountaineering's temperature ratings are right-on or conservative. I have 3 of their bags and use them to at least what their temperature ratings are. I have a Super Badger (+15F) that I use for mountaineering and snow camping. Any other manufacturer, you would want a zero degree bag or lower.

I was very comfortable in the Caribou in ~45 degree temps, in a bivy sack on a windy night. I was not wearing heavy fleece or a hat, so I could easily see the Caribou working to near freezing with some fleece and a hat.

The Caribou packs very small and quickly lofts when removed. WM includes an XXS stuff sack with the bag, but I tend to use a larger stuff sack so as not to compress it so much and keep my pack softer and more comfortable.

The newer micro-fiber bags should be even better and lighter than mine. I got a great close-out deal and could not pass it up. Since I tend to use a bivy sack, I didn't need the MF fabric.

I am 5'7 and I pretty much fill the 6' bag. Someone over 5'10 might want to consider the 6'6. It is a trim bag, but not cramped and the trim fit adds to its warmth.

I would definitely recommend it for almost any conditions above freezing.

If you balk at the price of Western Mountaineering bags... all I can say is that they are worth every penny.

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